Photographic developing apparatus



May 21, 1946. J. WYLLIE, .1R

PHOTOGRAPHIC DEVELOPING APPARATUS Original Filed Aug. l727, 1942 i 3 Sheets- Sheet 1 /M/EA/Toef W' W M Q Arme/vir May 21, 1946. J, wYLLlE, JR 2,400,675

PHOTOGRAPH I C DEVELOP ING APPARATUS Original Filed Aug. 27, 1942 3 Sheets-Sheet 2 35 "WIW,"

May 21, 1946. iJ. wYLLlE, JR

PHOTOGRAPHIC DEVELOPING APPARATUS Original Filed Aug. 27', 1942 3 Sheets-Sheet 3 ArroR/vgx Patented May 2l, 1946 PHoToGRArinc DEVELOPING APPARATUS John Wyllie, Jr., Detroit, Mich., assigner to Temprite Products Corporation, Detroit, Mich., a corporation of Michigan Original application August 27, 1942, Serial No.

456,327, now Patent No.

2,346,530, dated April 11, 1944. Divided and this application July 12, 1943, Serial No. 494,294

2 Claims. (Cl. (i2- 116) The present application is a division of my application Serial No. 456,327, led August 27, 1942.

The present invention relates to apparatus for developing photographic negatives and particularly to apparatus providing suitable temperature ratus in which the means for treating the negatives and the refrigerating apparatus are combined in a unitary, portable cabinet structure in which the necessary devices are compactly arranged for convenient use and servicing which is relatively light in weight and reliable in operation so that the apparatus is well suited for military or other field use as well as for fixed location use.

A further object of the invention is vthe provision of apparatus of the character stated in which the various developing, fixing and washing solutions are held in containers immersed in a mechanically-refrigerated cooling bath and in which such bath can readily be drained when the solution containers are not in use so that the bath chamber may be employed as a dry refrigerated space.

Another object of the invention is the provision of a unitary, mechanically-refrigerated cabinet apparatus which comprises a compartment having a light-tight closure, open-topped solution containers in the compartment adapted to receive nlm-winding mechanism of the doublereel, motor-driven type and an electric outlet fitting mounted in a wall of the compartment to afford an electric outlet connection within the compartment for the motor of such nlm-winding mechanism. I

Otherobjects of the invention, including some that are incidental or ancillary to those above noted, will be apparent from the description which follows.

With the various objects of the invention in view the invention consists in constructions, arrangements and combinations of parts Yas hereinafter explained in connection with the accompanying drawings -showing a preferred embodiment of the invention and as particularly pointed out in the claims.

In the drawings,

Fig: 1 is a perspective view of the entire apparatus.

Fig. 2 is a plan view on an enlarged scale of one of. the trays for developing prints.

Fig. 3 is a vertical section on the line 3-3 of Fig. 2.

Fig. 4 is a vertical section on the line 4-4 of Fig. 2.

Fig. 5 is an enlarged vertical section through the cabinet structure of the apparatus with some of the upper part of the structure Shown in elevation and' with some of the interior structure broken away to better illustrate details.

Fig. 6 is a plan view of the cabinet structure of the apparatus with its hinged lid or cover in open position.

Fig. 7 is a horizontal section taken through the cabinet Structure at the top of the lower, machine compartment of the cabinet and showing the apparatus in said compartment in plan.

Referring in detail to the construction .illustrated and rst to Fig. l, it will be noted that the apparatus comprises acabinet structure designated as an entirety by I and comprising means for developing photographic negatives, and separate developing devices of the tray type comprising a tray Support 2 and a series of trays 3, and 5 mounted thereon. The trays are opera- .tively associated with devices in the cabinet structure as will later be explained.

The cabinet I is constructed with front and rear walls 6 and 'I and end walls 8 and 9, all said walls being braced and strengthened by a horizontally-disposed angle iron frame I0 riveted to the side walls near the upper part thereof, by a similar angle iron frame Il riveted or welded to the side walls at the bottoms thereof and by a horizontal sheet metal partition I2 which is rigidly riveted or otherwise secured to the side walls and which divides the cabinet into upp-.r and lower compartments. The end wall 8 is provided with Ventilating openings as shown and the front wall 6 is fitted with a large removable panel 6El also provided with Ventilating openings. The open top of the cabinet, or of the upper compartment thereof, is closed by a hinged cover i3 which is provided with a soft rubber gasket I4 I to engage the top edges of the side walls to effect a light and liquid-tight closure of the upper compartment, trunk type fastening devices I5 being provided to secure the cover in closed position. The bottom wall and a substantial part of the sido 118 of the upper compartment of the cabinlt are lined with heat-insulating material II and within this insulation lining is tted a waterght tank l1, the top ilanged edges of which are secured to the frame I9. The tank I1 is preferably made of non-corrodible sheet metal and is surrounded by a refrigerant expansion coil I9, the turns of which are preferably soldered to the tank walls to secure good thermal contact therewith.

Within the tank I1 are arranged a series of three open-topped developing cans I9, I9 having hat bottoms and semi-circular end walls, as shown in Fig. 6, these cans being of the type adapted to receive a well-known, double-reel,

` motor-driven mechanism for the development of roll nlms.

Two tubular strut rods 29, are mounted across the tank I1 near the top thereof in position to extend between the middle can I9 and the end cans, respectively. On each of these struts a clamp or holder 2| is slidably mounted, said clamp including a, tubular part 2 I to engage the strut 20 and a transverse rod 2ib to engage the top edges of the adjacent cans I9, I9. When the clamps are in the central positions on struts 2l they serve to hold the cans I9 in position, but by sliding the clamps to the dotted line positions shown in Fig. 6 the cans are released for removal fromtank I1.

A water inlet pipe for tank I1 is provided at, 22 and an outlet pipe at 23, The tank is also provided with a large outlet drain pipe 24 which is tted with a manual plug valve 25 whichy when opened, permits the complete draining of the tank. The bottom wall of the tank I1 is fitted with a tubular housing 26 closed at its top and opening at its bottom through the bottom of the tank and horizontal wall I2, for a purpose which will later be explained.

It will be observed that the upper compartment of the cabinet extends substantially above the top of the tank I1 and this is to provide space or head room for the motor-driven reel devices previmlsly referred to. To provide for the energizing o! the reel motor. the cabinet is tted within the upper compartment with an electric cable conduit 21 which at its upper end terminates in an electric socket 29 into which the electric cable oi the reel motor may be plugged when roll films are to be developed. The socket outlet 28 is provided with a removable cap 29 to cover and protect the electric terminals from liquid which might otherwise accidentally enter the plug and short circuit the terminals.

In the lower compartment of the cabinet are arranged and mounted various refrigerating and water-circulating devices and accessories. 30 is a motor-driven refrigerant compressor of the hermetically sealed type suitably supported in known manner from the cabinet frame or wall structure. The refrigerant discharge opening of the compressor 30 is connected by means of conduit 3i with a condenser coil 32 which is mounted in front oi an opening in the rear wall 1 of the cabinet. In front of the condenser coil 32 is arranged a fan 33 driven by motor 34 and the coil 32 and fan 33 are provided with a suitable casing 36 to insure effective action of the fan on the coil. An air shield or director plate 3E is disposed In an upright position as shown in Fig. 'l to insure that the current of air drawn through the lower compartment of the cabinet by the fan 33 will also pass effectively over the casing of the motorcompressor unit 30.

The discharge end of the condenser coll 32 is connected by a conduit 31 with a refrigerant receiver 39, the outlet of which is connected by conduit 39 with an automatic expansion valve 40 and this valve is, in turn, connected by conduit 4I with the inlet end of the expansion coil I8 surrounding the tank I1, the outlet end of the coil I9 being connected by conduit 42 with the suction opening of compressor 30. For automatic control of the reirigerating apparatus the compressor motor is provided with an adjustable. automatically-operating thermostatic switch 43 having a. thermostatic bulb 43B disposed in the housing or well 2B of the tank I1.

The water-discharge conduit 23 of the tank I1 is connected by a flexible conduit section 44 with the inlet of a water-circulating pump 45 arranged to be driven by a motor 4B. The outlet of the pump 45 is connected by a. conduit 41 with a manually-operable throttle valve 43 mounted on the end wall 3 of the cabinet. The valve 49 is operatively connected with the tray developing devices as will presently be explained, Adjacent the automatic switch 43 at the front of the cabinet are `arranged a manual switch 49 controlling the electric circuit of the compressor motor and a manual switch 50 controlling the pump motor Returning now to the tray developing devices shown in Fig. 1, all of the three trays, with one sli-ght exception, are similar in construction and a description of the tray 4 shown in Figs. 2, 3 and 4 will suiiice for all of them. The tray proper 4 is pressed from a single piece of corrosion-resistant metal and has one corner formed with a pouring lip in conventional manner. Nearly the entire bottom wall of the tray is covered by a water jacket provided by a shallow pan 4b which is attached as by welding and soldering with a water-tight joint to the bottom of the tray. At its right end, as viewed in Fig. 3, the water jacket is provided with a water inlet conduit 4c and at its other end with an outlet conduit 4d.

The pan element 4b is formed with upwardlypressed ribs 4 and 4" which are staggered as shown in Fig. 2 so that water entering the jacket through conduit 4c is given a circuitous path through the jacket to the discharge conduit 4d.

As stated, the three trays are substantially alike, the only diiierence being that in the case of tray 5 the outlet conduit of the water jacket is turned to the right instead of to the left as in the case of trays 3 and 4.

As is shown in Fig. l, the water throttle valve 4B or the cabinet I is connected by a flexible rubber conduit 5I with the inlet conduit oi the tray 3. The outlet conduit of tray 3 is connected by a flexible rubber tube 52 to the inlet conduit of tray 4 and the outlet conduit of tray 4 is similarly connected by a rubber tube 53 with the inlet conduit of tray 5. Finally the outlet conduit of tray 5 is connected by a long flexible tube 54 with the water inlet pipe 22 which is carried by cabinet I and discharges into the tank I1. With the water jackets of trays 3y 4 and 5 connected as described to the water conduits of cabinet i, operation of the pump 45 serves to circulate water from tank I1, through the pump and the tray jackets and thence back to said tank.

It will be understood that the conduits 5I and 54 connecting the cabinet I with the tray apparatus may be of any suitable length to permit convenient disposition of the cabinet and tray equipment relative to each other. The apparatus is designed so that the cabinet and the tray apparatus can be disposed in separate adjacent dark rooms so that development of prints may be carrie@ on in one room quite independently of the development of films in the other room.

In the operation and use of the apparatus the tank I'I of the cabinet is supplied with an amount of water to submerge the developing cans I9 to a suitable depth and the cans I9, I9 are supplied with suitable working solutions constituting the developer, washing and fixing baths. The thermostatic switch 43 having been adjusted to provide the desired temperature for the water bath in the tank I1, the compressor motor is started by turning on the manual control switch 49. When the temperature of the water bath in tank I'I and of the working solutions in the cans I9 have all been lowered to the desired value (as shown by thermometer test), the apparatus is ready to receive and develop exposed photographic lm. Assuming the use of motor-driven developing machines of the type hereinbefore referred to, the film, which is wound on the reels of the motor-driven machine, is lowered into the developer can, the electric cable of the machine motor is plugged into the socket 2l and the cover of the cabinet is then closed so that light may be snapped on in the dark room during the winding and re-winding of the film in the developer solution. During the processing of the lm the latter is transferred from one solution to the other in the well known manner and throughout the processing the working solutions are maintained effectively at substantially uniform temperature, the automatic switch 43 serving to cut in and cut out the compressor motor as required.

During the development of films development of prints maybe carried on in the adjoining dark room in the trays 3, 4 and 5 in which the usual or desired working solutions are placed. When such print development is to be carried on the operator starts the pump motor 46 by turning on the switch 50. After the refrigerating apparatus and the pump have .been in operation for a sufiicient length of time the circulation of cooled water through the Water jackets of the trays 3,

4 and 5 lowers the temperature of the trays and the solutions therein to the desired working ternperature. Ii.' this temperature is to be substantially the same as that for developing the films the lthrottle valve 48 will be opened wide to permit relatively free ow of water through the tray waterjackets. If, however, the operator prefers to work the print solutions at a somewhat higher temperature than the film solutions, such higher temperature may be maintained by a 'throttling adjustment of the valve 48. It will be understood that the flexible conduit connections for the trays 8, 4 and 5 permit them to be freely lifted, tipped and emptied in the usual manner.

' structure having It will be seen that the film developing apparatus is highly compact with resultant minimizing of weight, an especially low weight being attained if the structural parts of the cabinet are formed of light weight metal such as aluminum alloy. Furthermore, the advantage of close temperature regulation for the print developingr trays is attained by the use of simple and convenient tray apparatus and without any substantial addition to the refrigeration apparatus for the cabinet other than the relatively simple motordriven water-circulating devices.

The facility with which the cabinet and tray apparatus, respectively, can Ibe installed in adjoining dark rooms or compartments and the compactness and comparatively light weight of the entire apparatus make it particularly well suited for installation in mobile truck or trailer units for use in the field. Also the eflicient way in which the cabinet and tray apparatus, respectively, can be used independently and simultaneously results in a marked saving of time in developing negatives and prints and this is advantageous particularly in the case of mobile units for military use.

It will be understood that the invention is not limited to the specific construction illustrated in the drawings but may be embodied in a Wide variety of constructions within the scope of the appended claims.

What is claimed is:

1. In photographic apparatus lfor developing roll film negatives, the combination of a cabinet therein a lower compartment and an upper compartment which has a top opening and a lid for effecting a light-tight closure thereof, said upper compartment forming an open-topped tank to hold a liquid cooling bath; a plurality of open-topped solution containers disposed in the said upper compartment to lbe cooled by the liquid bath therein, said solution= containers being of a depth greater than the width of the lm to .be developed and of horizontal dimensions to receive film-winding mechanism of the double-reel, motor-driven type; an

electric outlet socket fitting mounted in a wall of the upper compartment to afford an electric outlet connection within the compartment for the motor of the said film-winding mechanism; mechanical refrigerating apparatus comprising compressor and condenser units housed in the lower compartment of the cabinet and a refrigerant expansion coil associated with the cooling bath tank.

2. Photographic apparatus as claimed in claim 1 in which the electric socket tting comprises a detachable cover to protect the electric terminals of the fitting from liquid in the upper compartment of the cabinet.

JOHN WYLLIE, Jn. 

